CHICAGO (AP) — A yearlong study offers rigorous new evidence against using prescription opioids for chronic pain.

In patients with stubborn back aches or hip or knee arthritis, opioids worked no better than over-the-counter drugs or other nonopioids at reducing problems with walking or sleeping. And they provided slightly less pain relief,

Opioids tested included generic Vicodin, oxycodone or fentanyl patches although few patients needed the most potent opioids. Nonopioids included generic Tylenol, ibuprofen and prescription pills for nerve or muscle pain. The study randomly assigned patients...